In the petroleum industry, acoustic telemetry (reporting down-hole sensor readings) during the drilling process has been analyzed in detail in the open literature. However, acoustic telemetry within producing wells has not received much attention. In contrast to the relatively straightforward acoustic conditions during drilling, dispersion is a significant issue for down hole communication in a producing well. The ability to extend the range of an acoustic telemetry system in a producing well has economic value and, with better monitoring in producing wells, it may indirectly help prevent water table contamination as well as other environmental problems.